Catechesis: the Eucharist

The other kind of eating is oral and sacramental, when all who eat and drink the consecrated bread and wine in the Supper receive and partake of the true, essential body and blood of Christ orally. Believers receive it as a certain pledge and assurance that their sins are truly forgiven and that Christ dwells in them with his powers. Unbelievers receive it, too, but in their case as judgment and condemnation.—FC SD VII:63